The ornamental design for a wallet, as shown and described.
FIG. 1 is a front view of a wallet showing my new design;
FIG. 2 is a rear view of the wallet;
FIG. 3 is a right side view of the wallet;
FIG. 4 is a left side view of the wallet;
FIG. 5 is a top view of the wallet;
FIG. 6 is a bottom view of the wallet; and,
FIG. 7 is a front view thereof, shown in a position of use.
The broken lines shown on claimed surfaces depict stitching and form no part of the claimed design. The broken lines showing a strap and cards in FIG. 7 depict environment and form no part of the claim. All other broken lines depict portions of the article and form no part of the claim.